Overexpression of TiERF1 enhances resistance to sharp eyespot in transgenic wheat.
Wheat sharp eyespot, primarily caused by a soil-borne fungus Rhizoctonia cerealis, has become one of the most serious diseases of wheat in China. In this study, an ethylene response factor (ERF) gene from a wheat relative Thinopyrum intermedium, TiERF1, was characterized further, transgenic wheat lines expressing TiERF1 were developed, and the resistance of the transgenic wheat lines against R. cerealis was investigated. Southern blotting analysis indicated that at least two copies of the TiERF1 gene exist in the T. intermedium genome. Yeast one-hybrid assay indicated that the activation domain of TiERF1 is essential for activating the transcript of the reporter gene with the GCC-box cis-element. The TiERF1 gene was introduced into a Chinese wheat cultivar, Yangmai12, by biolistic bombardment. Results of PCR and Southern blotting analyses indicated that TiERF1 was successfully integrated into the genome of the transgenic wheat, where it can be passed down from the T0 to T4 generations. Quantitative reverse transcription-PCR analysis demonstrated that TiERF1 could be overexpressed in the stable transgenic plants, in which the expression levels of wheat pathogenesis-related (PR) genes primarily in the ethylene-dependent signal pathway, such as a chitinase gene and a beta-1,3-glucanase gene, were increased dramatically. Disease tests indicated that the overexpression of TiERF1 conferred enhanced resistance to sharp eyespot in the transgenic wheat lines compared with the wild-type and silenced TiERF1 plants. These results suggested that the overexpression of TiERF1 enhances resistance to sharp eyespot in transgenic wheat lines by activating PR genes primarily in the ethylene-dependent pathway.
Chen
Liang
L
National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China.
Zhang
ZengYan
Z
Liang
HongXia
H
Liu
HongXia
H
Du
LiPu
L
Xu
Huijun
H
Xin
Zhiyong
Z
D002688:Chitinases / Q000235:genetics / Q000378:metabolism; D005030:Ethylenes / Q000378:metabolism*; D015870:Gene Expression; D043326:Glucan 1,3-beta-Glucosidase / Q000235:genetics / Q000378:metabolism; D007113:Immunity, Innate; D010935:Plant Diseases / Q000382:microbiology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000502:physiology; D006109:Poaceae / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012232:Rhizoctonia / Q000472:pathogenicity; D014908:Triticum / Q000235:genetics / Q000276:immunology* / Q000382:microbiology / Q000502:physiology
D005030:Ethylenes; D010940:Plant Proteins; C036216:ethylene; D002688:Chitinases; D043326:Glucan 1,3-beta-Glucosidase